Posts Tagged ‘astrophysics’
“The universe is under no obligation to make sense to you”*…
Still, we try… In a consideration of three new books, the estimable Sean Carroll brings us up to date on the state of play…
Should scientists be embarrassed that they can’t settle on a definition for the Big Bang? The cosmologist Will Kinney describes it as the “physical theory of the hot infant universe,” while Wikipedia goes for the more elaborate “a physical theory that describes how the universe expanded from an initial state of high density and temperature.” The first refers only to early times, while the latter seems to extend to subsequent times as well. The physicist and science writer Tony Rothman offers the pithier “the universe’s origin,” the theoretical physicist Thomas Hertog suggests that it is the “primeval state” of cosmic history, and a NASA website gives us “the idea that the universe began as just a single point.” These seem to refer to one moment at the start of things, rather than the universe’s life since then.
All of these sources (except NASA, unfortunately) capture something correct. The confusion stems both from the inherent ambiguity of using ordinary language to describe novel scientific concepts and from the state of modern cosmology itself. Cosmology is the study of the universe on the largest scales. So it ignores details of stars and planets, focusing on galaxies and even bigger structures, up to the universe as a whole. Modern cosmology is only about a century old, as it wasn’t until the 1920s that astronomers determined that our own Milky Way is just one of a large number of galaxies and the origin and evolution of them all could be studied together. And it wasn’t until the 1990s that the field matured into the one that exists today, featuring precision measurements and ultralarge datasets.
Dealing as it does with some of the most profound questions about the nature of the cosmos, cosmological research has always involved a vigorous give-and-take between rampant speculation and unanticipated discoveries. Its practitioners have long been fond of spinning purportedly inviolate physical principles from their personal intuitions about how reality should work. But cosmology remains an empirical science—a cherished belief can be quickly swept away by a solid measurement.
The present moment in the science of cosmology is one of consolidation, as we have successfully incorporated the lessons of some impressive discoveries made near the turn of the twenty-first century. Yet crucially important questions remain unanswered, especially about what exactly happened at the onset of the expanding space that evolved into our contemporary universe. It is therefore a good time for books that take stock of where we are and what might come next, and that illustrate which puzzles modern physicists choose to take seriously.
This much we know: we live in a galaxy, the Milky Way, containing around 200 billion stars. There are something like a trillion galaxies in our observable universe, distributed almost uniformly through space. Stars and galaxies condensed out of an originally nearly smooth distribution of matter. Distant galaxies are moving apart from one another. Extrapolating backward, we reach a hot, densely packed configuration about 13.8 billion years ago. We can observe the remnants of this early period in nearly uniform cosmic background radiation coming from every direction in the sky.
The Big Bang model is precisely this general picture, of a universe that expands and cools out of a smooth, hot primordial state. It is well understood and almost universally accepted among modern cosmologists. The Big Bang event is a hypothetical moment when the whole thing might have started, at which the temperature and density are supposed to have been literally infinite—a “singularity,” in physics parlance. This is why the NASA definition above is unambiguously wrong: the Big Bang event has nothing to do with “a single point” in space—it refers to a moment in time.
Nobody knows whether there actually was such an event. To be honest, there probably wasn’t. Einstein’s theory of general relativity predicts that such a singularity would have happened, but most physicists think this signals a breakdown in the theory rather than being an accurate description of the physical world. A prediction of infinitely big physical quantities is apt to be a sign that we don’t have the right theoretical understanding…
[Starting with Einstein’s unification of space-time in 1905, Carroll explains the implications of quantum theory, in particular on the question of the expansion of the universe. Using the three (very different, but complementary) books under consideration, he unpacks the issues and demonstrates the way in which scientific theories about the origin of the universe often involve a vigorous give-and-take between speculation and discovery…]
… Taken together, these three books provide an illuminating view of the state of modern cosmology. There are established results, laudable efforts to connect promising hypotheses to a flood of incoming data, and brave speculations about the physical and metaphysical unknown. They are all notably well written for the genre and will keep readers entertained as they are educated. We can marvel at both how much scientists have learned about the universe and how much we have yet to understand.
The state of cosmology (and a look at science at work): “A First Time for Everything,” from @seanmcarroll.bsky.social in @nybooks.com.
* Neil deGrasse Tyson
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As we wrestle with reality, we might spare a thought for a major (if, in the end, incorrect) character in tale that Carroll tells: Fred Hoyle; he died on this date in 2001. A prominent astronomer, he formulated the theory of stellar nucleosynthesis. But he is rather better remembered for his controversial stances on other scientific matters—in particular his rejection of the (as Carroll observes, now widely-accepted) “Big Bang” theory– a term he coined, derisively, in an episode of his immensely-popular series The Nature of the Universe on BBC radio– and his promotion of panspermia as the source of life on Earth (or maybe the traffic was in the other direction?).
“The moon is a friend for the lonesome to talk to”*…
… and, as Bartosz Ciechanowski explains in a stunningly-illustrated essay, so much more. The moon affects our tides, our light, and even the Earth’s rotation– it’s no wonder that our constant companion has so haunted human culture…
… The Moon may be just an unassuming neighbor in the sky, but its presence affects our lives in many subtle ways. When it reflects sunlight off its scarred surface to guide the way in the darkness of night, or as it breathes life into oceans by rhythmically raising tides, or when it cloaks the Sun in a rare and awe-inspiring total solar eclipse, the Moon reminds us of the celestial world right outside of the safe confines of our planet.
Traveling through the cold and empty space by Earth’s side, the Moon is always just there. It may be barren and dull, but, undeterred by its own lifelessness, it never leaves us completely alone.
Perhaps the next time you catch a glimpse of the Moon’s shiny surface beaming in the night sky, you’ll see it a little differently – not as a mundane fixture of the heavens, but as a fellow companion that gently affects our own existence…
Absolutely fascinating– and beautiful: “Moon,” from @bciechanowski.bsky.social. Via @TheBrowser.
This is (R)D‘s second visit with Ciechanowski, who earlier helped us understand “Sound”; for more of his extraordinary work, visit his archive.
More on the moon and here.
* Carl Sandburg
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As we raise our eyes, we might send celestial birthday greetings to William Wilson Morgan; he was born on this date in 1906. As astronomer and astrophysicist, he was professor and astronomy director for the University of Chicago’s Yerkes Observatory in Wisconsin and managing editor of Astrophysical Journal. He was a leader in stellar and galaxy classification and helped prove the existence of spiral arms in our galaxy.
“Listening to both sides of a story will convince you that there is more to a story than both sides”*…
Regular readers will have deduced that I am something of a techno-optimist. While I worry that human misapplication (exploitation) of new technologies could create new dangers and/or further concentrate wealth and power in too few hands, I believe that emerging tech could– should– help humanity deal with many of its gravest challenges, certainly including climate change. At the same time, I am disposed to thinking about large issues/problems systemically.
Rianne Riemens shares neither of my enthusiasms; she sounds a critical note on techno-optimism, systems thinking– and more specifically, on the application of the latter to the former…
Today, American tech actors express optimistic ideas about how to fix the Earth and halt climate change. Such “green” initiatives have in common that they capture the world in systems and propose large systemic, and mostly technological, solutions. Because of their reliance on techno-fixes, representatives of Silicon Valley express an ideology of ecomodernism, which believes that human progress can be “decoupled” from environmental decline. In this article, I show how “whole-systems thinking” has become a key discursive element in today’s ecomodernist discourses. This discourse has developed from the 1960s onwards – inspired by cybernetic, ecological and computational theories – within the tech culture of California. This paper discusses three key periods in this development, highlighting key publications: the Whole Earth Catalog of the 1960s, the Limits to Growth report in 1972 and the cyberspace manifestoes of the mid 1990s. These periods are key to understand how techno-fixes became a popular answer to the climate crisis, eventually leading to a vision of the world as an ecosystem that can be easily controlled and manipulated, and of technological innovation as harmless and beneficial. I argue that “whole-systems” thinking offers a naive and misleading narrative about the development of the climate crisis, that offers a hopeful yet unrealistic perspective for a future threatened by climate change, built on a misconception of Earth as a datafied planet.
In “The Techno-Optimist Manifesto” (Citation2023) venture capitalist Marc Andreessen argues why we should all be techno-optimists, especially if we are worried about the future impact of the climate crisis. According to Andreessen, promoting unlimited technological progress is the only option: “there is no inherent conflict between the techno-capital machine and the natural environment”. If we generate unlimited clean energy, we can improve the natural environment, whereas a “technologically stagnant society ruins it” (Andreessen, Citation2023). This is possible, he writes, because technologies enable processes of dematerialization and will eventually lead to material abundance. And, “We believe the market economy is a discovery machine, a form of intelligence—an exploratory, evolutionary, adaptive system” (Andreessen, Citation2023). The manifesto thus conceptualizes technology as immaterial and the capitalist economy as an evolutionary system: it presents techno-fixes as a harmless form of environmental action, and economic growth as an inevitable process that political powers should not interfere with.
The “Techno-Optimist Manifesto” is an example of a form of techno-optimism that places full trust in the potential of capitalist tech companies to help humanity “innovate” its way out of a climate crisis. Andreessen (Citation2023) cites historical figures including Buckminster Fuller, Stewart Brand, Douglas Engelbart and Kevin Kelly as the inspiration for his manifesto, showing that the work of these figures and their communities is being remixed and reappropriated into the future visions of contemporary techno-optimists. In this article, I analyse how the belief in the environmental potential of techno-fixes is engrained in the ideology and history of “Silicon Valley” and is discursively constructed through a language of “whole-systems thinking”. I use the concept of whole-systems thinking as a lens to study how simplified notions taken from whole-systems theory and cybernetics played and still play a key role in techno-environmental discourse in the post-war era in the United States. I zoom in on three key events that help explain the origins and evolution of popular whole-systems thinking: the Whole Earth Catalog community led by Stewart Brand in the 1960s, the Limits to Growth report by the Club of Rome in the 1970s and the cyberlibertarian community in the 1990s. I will show how a new language emerged that used simplified notions of systems-thinking to promote the idea that technology would help understand, manage and save a planet in peril.
Through a discourse analysis of primary sources and literature review I present a critical reading of these events in the light of today’s techno-optimistic environmental discourse. My corpus exists of a number of primary sources, including the aforementioned “Techno-Optimist Manifesto” (2023), Limits to Growth report (Meadows et al., Citation1972), editions of the Whole Earth Catalog and CoEvolution Quarterly, Barlow’s Declaration of the Independence of Cyberspace (1996), texts by Kevin Kelly (Citation1998) and Stewart Brand (Citation2009) and An Ecomodernist Manifesto (Asafu-Adjaye et al., Citation2015). I have discursively analysed these sources for their discussion of systems thinking as well as environmental concerns. By analysing how whole-systems thinking became a popular way of addressing environmental issues, I aim to provide a “post-war genealogy” (Pedwell Citation2022) of the term and critique today’s promises about how tech can save the climate. As Johnston (Citation2020) has argued, tracing the development of a cultural perception of trust in techno-fixes reveals a complex and multi-sided history. I claim that the environmental dimension of techno-optimistic discourses requires a critical reconsideration of the ideological underpinnings of Silicon Valley, described as the “Californian Ideology” by Barbrook and Cameron (Citation1996). I will demonstrate how ecomodernism, including its belief that human progress can be “decoupled” from environmental decline, allows us to better understand, and critique, the environmental ideology of Silicon Valley.
I will first expand on contemporary ecomodernism and present my thesis that “decoupling” nature from culture has come to underlie whole-systems thinking in contemporary techno-optimistic discourse. In the following three sections, I highlight a few historical moments to demonstrate the development of the cultural perception of techno-fixes, specifically as a means of managing the environment. I show how whole-systems thinking became popularized by the Whole Earth community, got incorporated in environmental debates through the Limits to Growth report and is reflected in cyberutopian dreams about immaterial societies. Building on my necessarily brief history, I argue that techno-fixes can be strategically presented as ideal solutions if the world and environment are imagined as simple systems and technology as immaterial and harmless. Finally, I return to contemporary US tech culture and argue that it is shaped by, and co-shapes, the ideology of ecomodernism in which nature and culture are decoupled. I conclude that this worldview expresses itself today in corporate visions, resulting in a false hope about how to innovate our way out of the climate crisis…
Eminently worth reading in full (if in the end, as for me, less as a wholesale rejection of techno-optimism and systems thinking than as a cautionary counterweight): “Fixing the earth: whole-systems thinking in Silicon Valley’s environmental ideology,” from @WeAreTandF.
(image above: source)
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As we tangle with tech, we might pause to remember a man who bridged our understanding of the systems of the world from one paradigm to another: Sir Arthur Stanley Eddington, OM, FRS; he died in this date in 1944. An astrophysicist, mathematician, and philosopher of science known for his work on the motion, distribution, evolution and structure of stars, Eddington is probably best remembered for his relationship to Einstein: he was, via a series of widely-published articles, the primary “explainer” of Einstein’s Theory of General Relativity to the English-speaking world; and he was, in 1919, the leader of the experimental team that used observations of a solar eclipse to confirm the theory.
“I was a peripheral visionary. I could see the future, but only way off to the side.”*…
As Niels Bohr said, “prediciton is hard, especially about the future.” Still, we can try…
While the future cannot be predicted with certainty, present understanding in various scientific fields allows for the prediction of some far-future events, if only in the broadest outline. These fields include astrophysics, which studies how planets and stars form, interact, and die; particle physics, which has revealed how matter behaves at the smallest scales; evolutionary biology, which studies how life evolves over time; plate tectonics, which shows how continents shift over millennia; and sociology, which examines how human societies and cultures evolve.
The far future begins after the current millennium comes to an end, starting with the 4th millennium in 3001 CE, and continues until the furthest reaches of future time. These timelines include alternative future events that address unresolved scientific questions, such as whether humans will become extinct, whether the Earth survives when the Sun expands to become a red giant and whether proton decay will be the eventual end of all matter in the Universe…
A new pole star, the end of Niagara Falls, the wearing away of the Canadian Rockies– and these are just highlights from the first 50-60 million years. Read on for an extraordinary outline of what current science suggests is in store over the long haul: “Timeline of the far future,” a remarkable Wikipedia page.
Related pages: List of future astronomical events, Far future in fiction, and Far future in religion.
* Steven Wright
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As we take the long view, we might send grateful birthday greetings to the man who “wrote the book” on perspective (a capacity analogically handy in the endeavor featured above), Leon Battista Alberti; he was born on this date in 1404. The archetypical Renaissance humanist polymath, Alberti was an author, artist, architect, poet, priest, linguist, philosopher, cartographer, and cryptographer. He collaborated with Toscanelli on the maps used by Columbus on his first voyage, and he published the the first book on cryptography that contained a frequency table.
But he is surely best remembered as the author of the first general treatise– De Pictura (1434)– on the the laws of perspective, which built on and extended Brunelleschi’s work to describe the approach and technique that established the science of projective geometry… and fueled the progress of painting, sculpture, and architecture from the Greek- and Arabic-influenced formalism of the High Middle Ages to the more naturalistic (and Latinate) styles of Renaissance.
“I have not yet lost a feeling of wonder, and of delight, that the delicate motion should reside in all the things around us”*…
The proton, the positively charged particle at the heart of the atom, is an object of unspeakable complexity, one that changes its appearance depending on how it is probed…
“This is the most complicated thing that you could possibly imagine,” said Mike Williams, a physicist at the Massachusetts Institute of Technology. “In fact, you can’t even imagine how complicated it is.”
The proton is a quantum mechanical object that exists as a haze of probabilities until an experiment forces it to take a concrete form. And its forms differ drastically depending on how researchers set up their experiment. Connecting the particle’s many faces has been the work of generations. “We’re kind of just starting to understand this system in a complete way,” said Richard Milner, a nuclear physicist at MIT.
As the pursuit continues, the proton’s secrets keep tumbling out. Most recently, a monumental data analysis published in August found that the proton contains traces of particles called charm quarks that are heavier than the proton itself.
The proton “has been humbling to humans,” Williams said. “Every time you think you kind of have a handle on it, it throws you some curveballs.”
Recently, Milner, together with Rolf Ent at Jefferson Lab, MIT filmmakers Chris Boebel and Joe McMaster, and animator James LaPlante, set out to transform a set of arcane plots that compile the results of hundreds of experiments into a series of animations of the shape-shifting proton…
Charlie Wood (and Merrill Sherman) have incorporated that work into an attempt to unveil the particle’s secrets: “Inside the Proton, the ‘Most Complicated Thing You Could Possibly Imagine’,” from @walkingthedot in @QuantaMagazine.
* Edmund Burke
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As we ponder presumptive paradoxes, we might send insightful birthday greetings to David Schramm; he was born on this date in 1945. A theoretical astrophysicist, he established the field of particle astrophysics, a branch of particle physics that studies elementary particles of astronomical origin and their relation to astrophysics and cosmology. He was particularly well known for the study of Big Bang nucleosynthesis and its use as a probe of dark matter and of neutrinos. And he made important contributions to the study of cosmic rays, supernova explosions, heavy-element nucleosynthesis, and nuclear astrophysics generally.
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